This is an application for renewal of the Medical Scientist Training Program at The Johns Hopkins University School of Medicine. The Program, now in its 29th year, seeks to train MD-PhD students for positions of leadership in academic medicine and medical research. During the previous funding period, applications increased steadily to a record level of 574. Interviews are extended to less than 20% of these students;applicants invited for interviews have outstanding academic records (mean GPA 3.9), excellent MCAT scores (average single test score 12.1), significant laboratory research experience, and high motivation for careers in biomedical research and clinical medicine. Approximately 10 to 12 students enter the Program each year and on average 10 students receive MSTP awards. The average length of study for the combined degrees is between 7-8 years. There are currently 92 MD/PhD students in the Program;54 have MSTP awards. Four have individual NRSA awards. Enrollment of underrepresented minorities has increased to 32%. Students generally take two years of preclinical science courses and then enroll in a graduate program for approximately four years. During this time, students take advanced courses and select from a pool of over 500 potential mentors. Mentors selected have well supported research programs ($1,500,000 average ADC) and substantial training experience (average of 15 prior trainees). Students complete thesis research, publishing an average of 6.3 peer-reviewed papers, before returning to complete the remaining required clinical clerkships and electives in medical school. The MSTP Director is a Johns Hopkins faculty member who is also an active investigator. The Director heads a 29-member MD-PhD Committee that admits applicants and formulates policies for the Program. The committee members also assist the Director in advising trainees and evaluating student progress. The Program has been highly successful in fulfilling the goals initially set forth by the NIH. Since the inception of the Johns Hopkins MSTP training grant, 232 MD/PhD students have graduated from the Program. Of these, 165 had MSTP support;163 have completed postgraduate training and have begun their careers. Of these, 88% are in medical research positions. This includes those in academic medicine (69%), those at research institutes such as the NIH (7%), and those in the pharmaceutical or biotech industries (12%).